There are known force measuring devices or load cells comprising a relatively rigid body having regions of a reduced thickness where force sensitive elements are applied with upon exertion of forces respond to strain or shearing forces of the body by changing their electric characteristic. A typical example for such elements is a strain gauge. Other types of such elements are piezo-electric and piezo-resistive elements. In many applications of such load cells forces directed vertically onto such cells are to be exactly measured. However, usually the applied forces are not strictly vertical such that the load cell is loaded by force components in horizontal direction. These horizontal force components cause misreadings of the measurement; furthermore, there is a danger of damaging the load cell. Known load cells have relatively large height and an additional clearance is necessary for arranging supporting elements used for eliminating horizontal force components.
The UK Patent Application No. 2 145 831 discloses a self-aligning weighing platform which is supported by force-transmitting assemblies including a slider which is movable along a base surface. A rocker pin housed in generally cylindrical recesses at the bottom side of a load cell beam and in the slider transmits force therebetween. Using a specific method the weighing platform is self-aligned. the load cell beam is of a generally parallele piped from a retainer member being screwed to its bottom side embracing the slider for at least partial movement with the load cell beam. Thus, as mentioned before various separate elements are necessary to properly support the load cell beam.
The UK patent specification No. 1,049,151 discloses a force measuring instrument comprising a pair substantially parallel end plates seperated by at least three spaced columns which may be elastically compressed when a force is applied.
The German Patent Application Publication No. 22 57 009 discloses a device for introducing a force to a load cell using a specific force introduction member consisting of two support parts having generally plane opposing surfaces. Balls are inserted into spheric recesses provided in the opposing surfaces of the two support parts.
The German Patent Application Publication No. 25 46 890 relates to an assembly and protecting arrangement for load cells or weighing apparatuses using a rocker pin with rounded face surfaces bearing on plane surfaces of a base plate and of a weighing platform.